System and method for determining image resolution using MICR characters

ABSTRACT

A system and method for determining the image resolution of a check image using MICR characters. The disclosed system includes an extracting system for extracting a magnetic ink code recognition (MICR) code line from the document image, wherein the extracting system provides coordinate values for each of a plurality of MICR characters in the MICR code line; a calculating system for calculating a set of resolution values based on the coordinate values of the MICR characters; and a statistical analysis system that calculates a representative resolution value from the set of resolution values.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates generally to image processing, and relatesmore specifically to a system and method for determining imageresolution using MICR (magnetic ink code recognition) characters.

2. Related Art

The finance industry has adopted electronic images of checks as a keycomponent of check processing. The recent passage of the Check 21 Act,which allows institutions to process check images, as opposed to theactual paper document, further attests to the progressively increasinguse of such images. As such, the ability to efficiently process highvolumes of check images is a critical requirement for such institutions.

To enable the use of several image processing technologies, such as OCR(optical character resolution), etc., the imaging resolution of theimaged document is required. In general, image resolution is ameasurement of pixels/inch. Occasionally, at the time of capture, theimaging resolution is either not recorded in the image header or isrecorded incorrectly. Without the resolution, the document cannot beprocessed. Thus, it becomes necessary that the imaging resolution beestablished by some independent means.

To date, no one has addressed this problem. Accordingly, a need existsfor a process that can determine the imaging resolution of an imageddocument, such as a check.

SUMMARY OF THE INVENTION

The present invention addresses the above-mentioned problems, as well asothers by providing a system and method for determining image resolutionusing the MICR characters printed on the imaged document. In a firstaspect, the invention provides a system for determining an imageresolution of a document image, comprising: an extracting system forextracting a magnetic ink code recognition (MICR) code line from thedocument image, wherein the extracting system provides coordinate valuesfor each of a plurality of MICR characters in the MICR code line; acalculating system for calculating a set of resolution values based onthe coordinate values of the MICR characters; and a statistical analysissystem that calculates a representative resolution value from the set ofresolution values.

In a second aspect, the invention provides a program product stored on acomputer readable medium for determining an image resolution of adocument image, comprising: program code configured for extracting amagnetic ink code recognition (MICR) code line from the document image;program code configured for providing coordinate values for each of aplurality of MICR characters in the MICR code line; program codeconfigured for calculating a set of resolution values based on thecoordinate values of the MICR characters; and program code configuredfor calculating a final resolution value from the set of resolutionvalues.

In a third aspect, the invention provides a computerized method fordetermining an image resolution of a document image, comprising:extracting a magnetic ink code recognition (MICR) code line from thedocument image; determining coordinate values for each of a plurality ofMICR characters in the MICR code line; calculating a set of resolutionvalues based on the coordinate values of the MICR characters; andcalculating a final resolution value from the set of resolution values.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of this invention will be more readilyunderstood from the following detailed description of the variousaspects of the invention taken in conjunction with the accompanyingdrawings in which:

FIG. 1 depicts a diagram of a system for determining image resolution inaccordance with present invention.

FIG. 2 depicts a table displaying coordinate and resolution values of afirst image in accordance with present invention.

FIG. 3 depicts a graph of the X coordinate resolution values of thefirst image.

FIG. 4 depicts a graph of the Y coordinate resolution values of thefirst image.

FIG. 5 depicts a table displaying coordinate and resolution values of asecond image in accordance with present invention.

FIG. 6 depicts a graph of the X coordinate resolution values of thesecond image.

FIG. 7 depicts a graph of the Y coordinate resolution values of thesecond image.

The drawings are merely schematic representations, not intended toportray specific parameters of the invention. The drawings are intendedto depict only typical embodiments of the invention, and thereforeshould not be considered as limiting the scope of the invention. In thedrawings, like numbering represents like elements.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, FIG. 1 depicts an illustrative computersystem 10 that inputs a check image 14 and outputs a resolution 30 ofthe check image 14. Check image 14 may comprise a bitonal, e.g., blackwhite, image, or a grayscale image. Computer system 10 generallyincludes a processor 17, input/output (I/O) 16, and memory 12. Stored inmemory 12, e.g., as a program product, is a system 18 for determiningimage resolution. As described in further detail below, the system 18for determining image resolution determines the resolution 30 of thecheck image 14 by examining the MICR (magnetic ink characterrecognition) code line 15 on the check. Once the resolution 30 iscalculated, the information can be fed into an image processing system32 (e.g., optical character recognition, storage, etc.), where the checkimage 14 can be further processed.

As is known in the art, a MICR code line 15 complying with the E13Bstandard is printed on every check. The E13B standard dictates thespacing and height of the characters in the code line. Namely, thestandard dictates a right justified spacing between characters of 0.125inches and a character height of 0.117 inches. Accordingly, by analyzingthe corresponding image pixels of the MICR code line 15 in the checkimage 14, the image resolution (i.e., pixels/inch or dots per inch“dpi”) of the check image 14 can be readily calculated in bothhorizontal (X) and vertical (Y) directions. Note that while theinvention is described with reference to determining a resolution of acheck image 14 by analyzing the MICR code line 15, the invention couldbe used to determine a resolution of any imaged document that containsMICR characters or the like that have known spatial characteristics(e.g., E13B).

In the illustrative embodiment of FIG. 1, the system 18 for determiningimage resolution includes a system 20 for extracting MICR code linedata, a resolution calculations system 22, a statistical analysis system24, and a tolerance system 26. The system 20 for extracting MICR codeline data can use any known means for locating the MICR code line 15 onthe check image 14, and extracting the MICR characters and theircoordinates from the check image 14. For example, connected componentanalysis, which is a well know technique for locating chunks ofconnected pixel data on a black white image, may be utilized.

Data from an illustrative check image 14 is shown in FIG. 2, whichincludes a table that shows the MICR characters 34 appearing on thecheck, MICR character coordinates 36 within the check, and resultingresolution values 38 for the MICR code line 15. In this case, the MICRcode line data 15 is made up of 32 MICR characters as shown in the firsttwo columns, and the MICR character coordinates 36, which comprise a topleft X coordinate, a top left Y coordinate, a bottom right X coordinate,and a bottom right Y coordinate.

The horizontal distance or “pitch” between each character in the checkimage 14 is calculated as the difference between bottom right Xcoordinate of adjacent characters, i.e., the control spacing per ANSIspecification. This value is determined as follows:BottomRx(n+1)−BottomRx(n),where n is nth character in the printed sequence of characters in theMICR code line 15. The height of each character can for example becalculated as the vertical difference between the bottom right Ycoordinate and the top left Y coordinate for the character, i.e.,BottomRy(n)−TopLy(n).Given the ability to determine these measurements, a set of resolutionvalues 38 can be determined comprised of the resolution data, Diff Rxand Diff Ry, whereDiff Rx=(BottomRx(n+1)−BottomRx(n))*8,which represents the distance between bottom right coordinates ofsuccessive characters multiplied by 1/0.125 (i.e., 8). Accordingly, DiffRx represents eight times the number of calculated pixels in 0.125inches of length, or the pixels per inch in the horizontal direction,i.e., the X direction image resolution of two successive characters.Diff Ry=(BottomRy(n)−TopLy(n))*8.55,

which represents the height of a given character n multiplied by 1/0.117(i.e., 8.55). Diff Ry represents 8.55 times the number of calculatedpixels in 0.117 inches of height, or the pixels per inch in the verticaldirection, i.e., the Y direction image resolution for each character.

Once the resolution values 38 (Diff Rx and Diff Ry) are made,statistical analysis system 24 may be utilized to eliminate any bad datapoints and determine a representative value for both Diff Rx and DiffRy. Because the fields of a MICR code line can be printed at differenttimes and be spaced from each other is a non-regimented fashion,statistical anomalies may be introduced among the resolution values 38,particularly for the Diff Rx values, which relate to the horizontalpitch. For example, as shown in FIG. 3, a number of bad data points(i.e., spikes) are apparent when the Diff Rx values are plotted for eachcharacter pair. Statistical analysis system 24 is utilized to eliminatesuch anomalies.

One illustrative method for achieving this involves determining a medianvalue of the resolution values 38. A median value is determined, e.g.,by ordering all of the resolution values 38 in descending order and thenidentifying the center of the population. For the Diff Rx example shownin FIGS. 2 and 3, this would result in an ordering of (792, 720, 472,472, 248, 248, 248, 240, 240, 240, 240, 240, 240, 240, . . . 232, 232,232, 232), with center of the population being 240. Thus, the bad datapoints 792, 720, 472, 472, which likely relate to the distances betweenprinted fields in the MICR code line, have been essentially eliminatedusing this analysis.

Once a representative value for both the Diff Rx and Diff Ry areestablished, tolerance system 26 can be implemented to identify aresolution 30 by matching the representative values to known industrystandard resolution operating points. As is known in the art of checkimaging, there exist a number of practiced operating points used forresolution, e.g., 200 and 240 are common operating points for blackwhite images. In the plot shown in FIG. 3, the representative value, inthis case 240, is matched against the set of possible resolutionoperating points (+/− a tolerance, e.g., 15) to determine a matchingoperating point. Tolerance system 26, which sets the tolerance value, isused to accommodate for scanning inaccuracies, bitonal conversioninaccuracies, etc. In this case, assuming two possible operating pointsof 200 and 240, and a tolerance of +/−15, the representative value of240 would be matched against both a first tolerance range of 185-215(for operating point 200) and a second tolerance range of 225-255 (foroperating point 240). In this example, because the representative valuefalls within the second tolerance range, the X direction resolutionwould be 240 dpi.

Similarly, as shown in FIG. 4, Diff Ry is plotted for each character. Arepresentative (e.g., median) value of 247.95 is determined, which wouldmatch the tolerance range of 225-255, resulting in a calculatedresolution of 240. Thus, for the example shown in FIGS. 2-4, it can bededuced the resolution is 240 for both the X and Y directions. Thecalculated resolution values for one or both of the X and Y directionsmay be outputted as the final resolution 30.

FIGS. 5-7 show a second example where the representative values of DiffRx and Diff Ry are 200 and 205.2 respectively. In this case, it can bereadily deduced that the matching operating point would be 200 in bothdirections, thus resulting in a calculated resolution of 200 dpi.

It should also be understood that computer system 10 may comprise anytype of computer, e.g., workstation, laptop, handheld device, PDA, cellphone, smart appliance, etc. The processor 17 may comprise a singleprocessing unit, or may be distributed across one or more processingunits in one or more locations. Memory 12 may comprise any known type ofdata storage and/or transmission media, including magnetic media,optical media, random access memory (RAM), read-only memory (ROM), etc.Moreover, similar to the processor, the memory 12 may reside at a singlephysical location, comprising one or more types of data storage, or bedistributed across a plurality of physical systems in various forms.

I/O 16 may comprise any system for exchanging information to/from anexternal source. External devices/resources may comprise any known typeof external device, including a scanner, a CRT, LED screen, handhelddevice, keyboard, mouse, voice recognition system, speech output system,printer, monitor/display, facsimile, pager, etc. A bus provides acommunication link between each of the components in computer system 10,and likewise may comprise any known type of transmission link, includingelectrical, optical, wireless, etc. In addition, although not shown,other components, such as cache memory, communication systems, systemsoftware, etc., may be incorporated into computer system 10.

The system 18 for determining image resolution may be stored in thecomputer system memory 12, such that the functional components areprovided as a computer program product. It should be appreciated thatthe teachings of the present invention can be offered as a businessmethod on a subscription or fee basis. For example, system 18 fordetermining image resolution could be created, maintained, supported,and/or deployed by a service provider that offers the functionsdescribed herein for customers.

It should also be understood that the present invention can be realizedin hardware, software, a propagated signal, or any combination thereof.Any kind of computer/server system(s)—or other apparatus adapted forcarrying out the methods described herein—is suited. A typicalcombination of hardware and software could be a general purpose computersystem with a computer program that, when loaded and executed, carriesout the respective methods described herein. Alternatively, a specificuse computer, containing specialized hardware for carrying out one ormore of the functional tasks of the invention, could be utilized. Thepresent invention can also comprise a computer-readable medium forstoring a computer program product or a propagated signal, whichcomprises all the respective features enabling the implementation of themethods described herein, and which—when loaded in a computer system—isable to carry out these methods. Computer program, propagated signal,software program, program, or software, in the present context mean anyexpression, in any language, code or notation, of a set of instructionsintended to cause a system having an information processing capabilityto perform a particular function either directly or after either or bothof the following: (a) conversion to another language, code or notation;and/or (b) reproduction in a different material form.

The foregoing description of the preferred embodiments of this inventionhas been presented for purposes of illustration and description. It isnot intended to be exhaustive or to limit the invention to the preciseform disclosed, and obviously, many modifications and variations arepossible. For example, the invention could be implemented by determiningeither or both the horizontal and vertical resolution. Suchmodifications and variations that may be apparent to a person skilled inthe art are intended to be included within the scope of this inventionas defined by the accompanying claims.

1. A computerized method for determining an image resolution of adocument image, comprising: extracting a magnetic ink code recognition(MICR) code line from the document image; determining coordinate valuesfor each of a plurality of MICR characters in the MICR code line;calculating a set of resolution values based on the coordinate values ofthe MICR characters and a known spatial characteristic of a MICRcharacter set; and calculating a final resolution value from the set ofresolution values, wherein the final resolution value is given as anumber of pixels per unit length.
 2. The method of claim 1, wherein thestep of extracting the MICR code line utilizes connected componentanalysis.
 3. The method of claim 1, wherein the coordinate valuesinclude horizontal and vertical data.
 4. The method of claim 1, whereinthe step of calculating the set of resolution values determines ahorizontal resolution value for sequential MICR characters in accordancewith the equation:(BottomRx(n+1)−BottomRx(n))*8, where BottomRx(n) is a bottom righthorizontal direction coordinate of an nth character.
 5. The method ofclaim 1, wherein the step of calculating the set of resolution valuesdetermines a vertical resolution value for each MICR character inaccordance with the equation:(BottomRy(n)−TopLy(n))*8.55, where BottomRy(n) is a bottom rightvertical direction coordinate of an nth character and TopLy(n) is a topleft vertical direction coordinate of the nth character.
 6. The methodof claim 1, wherein the step of calculating a final resolution valueincludes the step of matching a median value from the set of resolutionvalues with a set of known resolution operating points to determine thefinal resolution value.
 7. The method of claim 6, wherein the step ofcalculating a final resolution value incorporates a tolerance value intothe matching step.